Background

Afatinib is an oral, irreversible ErbB family blocker that has shown activity in epidermal growth factor receptor (EGFR)-mutated lung cancer. We hypothesized that the agent would have greater antitumor activity compared with cetuximab in recurrent or metastatic (R/M) head and neck squamous cell carcinoma (HNSCC) patients, whose disease has progressed after platinum-containing therapy.

Patients and methods

An open-label, randomized, phase II trial was conducted in 43 centers; 124 patients were randomized (1 : 1) to either afatinib (50 mg/day) or cetuximab (250 mg/m(2)/week) until disease progression or intolerable adverse events (AEs) (stage I), with optional crossover (stage II). The primary end point was tumor shrinkage before crossover assessed by investigator (IR) and independent central review (ICR).

Results

A total of 121 patients were treated (61 afatinib, 60 cetuximab) and 68 crossed over to stage II (32 and 36 respectively). In stage I, mean tumor shrinkage by IR/ICR was 10.4%/16.6% with afatinib and 5.4%/10.1% with cetuximab (P = 0.46/0.30). Objective response rate was 16.1%/8.1% with afatinib and 6.5%/9.7% with cetuximab (IR/ICR). Comparable disease control rates were observed with afatinib (50%) and cetuximab (56.5%) by IR; similar results were seen by ICR. Most common grade ≥3 drug-related AEs (DRAEs) were rash/acne (18% versus 8.3%), diarrhea (14.8% versus 0%), and stomatitis/mucositis (11.5% versus 0%) with afatinib and cetuximab, respectively. Patients with DRAEs leading to treatment discontinuation were 23% with afatinib and 5% with cetuximab. In stage II, disease control rate (IR/ICR) was 38.9%/33.3% with afatinib and 18.8%/18.8% with cetuximab.

Conclusion

Afatinib showed antitumor activity comparable to cetuximab in R/M HNSCC in this exploratory phase II trial, although more patients on afatinib discontinued treatment due to AEs. Sequential EGFR/ErbB treatment with afatinib and cetuximab provided sustained clinical benefit in patients after crossover, suggesting a lack of cross-resistance.

Background

In the phase III LUX-Head & Neck 1 (LUX-H&N1) trial, second-line afatinib significantly improved progression-free survival (PFS) versus methotrexate in patients with recurrent/metastatic head and neck squamous cell carcinoma (R/M HNSCC). Here, we evaluated association of prespecified biomarkers with efficacy outcomes in LUX-H&N1.

Patients and methods

Randomized patients with R/M HNSCC and progression following ≥2 cycles of platinum therapy received afatinib (40 mg/day) or methotrexate (40 mg/m2/week). Tumor/serum samples were collected at study entry for patients who volunteered for inclusion in biomarker analyses. Tumor biomarkers, including p16 (prespecified subgroup; all tumor subsites), EGFR, HER2, HER3, c-MET and PTEN, were assessed using tissue microarray cores and slides; serum protein was evaluated using the VeriStrat® test. Biomarkers were correlated with efficacy outcomes.

Results

Of 483 randomized patients, 326 (67%) were included in the biomarker analyses; baseline characteristics were consistent with the overall study population. Median PFS favored afatinib over methotrexate in patients with p16-negative [2.7 versus 1.6 months; HR 0.70 (95% CI 0.50-0.97)], EGFR-amplified [2.8 versus 1.5 months; HR 0.53 (0.33-0.85)], HER3-low [2.8 versus 1.8 months; HR 0.57 (0.37-0.88)], and PTEN-high [1.6 versus 1.4 months; HR 0.55 (0.29-1.05)] tumors. Afatinib also improved PFS in combined subsets of patients with p16-negative and EGFR-amplified tumors [2.7 versus 1.5 months; HR 0.47 (0.28-0.80)], and patients with p16-negative tumors who were EGFR therapy-naïve [4.0 versus 2.4 months; HR 0.55 (0.31-0.98)]. PFS was improved in afatinib-treated patients who were VeriStrat 'Good' versus 'Poor' [2.7 versus 1.5 months; HR 0.71 (0.49-0.94)], but no treatment interaction was observed. Afatinib improved tumor response versus methotrexate in all subsets analyzed except for those with p16-positive disease (n = 35).

Conclusions

Subgroups of HNSCC patients who may achieve increased benefit from afatinib were identified based on prespecified tumor biomarkers (p16-negative, EGFR-amplified, HER3-low, PTEN-high). Future studies are warranted to validate these findings.

Clinical trial registration

NCT01345682.

Background

In the phase III LUX-Head & Neck 1 (LHN1) trial, afatinib significantly improved progression-free survival (PFS) versus methotrexate in recurrent and/or metastatic (R/M) head and neck squamous cell carcinoma (HNSCC) patients progressing on/after platinum-based therapy. This report evaluates afatinib efficacy and safety in prespecified subgroups of patients aged ≥65 and <65 years.

Patients and methods

Patients were randomized (2:1) to 40 mg/day oral afatinib or 40 mg/m(2)/week intravenous methotrexate. PFS was the primary end point; overall survival (OS) was the key secondary end point. Other end points included: objective response rate (ORR), patient-reported outcomes, tumor shrinkage, and safety. Disease control rate (DCR) was also assessed.

Results

Of 483 randomized patients, 27% (83 afatinib; 45 methotrexate) were aged ≥65 years (older) and 73% (239 afatinib; 116 methotrexate) <65 years (younger) at study entry. Similar PFS benefit with afatinib versus methotrexate was observed in older {median 2.8 versus 2.3 months, hazard ratio (HR) = 0.68 [95% confidence interval (CI) 0.45-1.03], P = 0.061} and younger patients [2.6 versus 1.6 months, HR = 0.79 (0.62-1.01), P = 0.052]. In older and younger patients, the median OS with afatinib versus methotrexate was 7.3 versus 6.4 months [HR = 0.84 (0.54-1.31)] and 6.7 versus 6.2 months [HR = 0.98 (0.76-1.28)]. ORRs with afatinib versus methotrexate were 10.8% versus 6.7% and 10.0% versus 5.2%; DCRs were 53.0% versus 37.8% and 47.7% versus 38.8% in older and younger patients, respectively. In both subgroups, the most frequent treatment-related adverse events were rash/acne (73%-77%) and diarrhea (70%-80%) with afatinib, and stomatitis (43%) and fatigue (31%-34%) with methotrexate. Fewer treatment-related discontinuations were observed with afatinib (each subgroup 7% versus 16%). A trend toward improved time to deterioration of global health status, pain, and swallowing with afatinib was observed in both subgroups.

Conclusions

Advancing age (≥65 years) did not adversely affect clinical outcomes or safety with afatinib versus methotrexate in second-line R/M HNSCC patients.

Clinical trial registration

NCT01345682 (ClinicalTrials.gov).